The invention relates to a process for extracting (pack) blanks made of (thin) cardboard from a blank magazine, especially for producing hinge-lid boxes for holding cigarettes, in which blank stacks in the blank magazine are held in the region of a (lower) extraction opening solely by two supporting means (supporting fingers) situated on two opposite sides of said extraction opening, said supporting means resting against the free (bottom) side of the blank which is to be extracted. The invention furthermore relates to an apparatus for extracting and transporting away the (pack) blanks.
The invention is concerned with the handling of prefabricated, specifically pre-punched blanks within a packing machine. For making packs of thin cardboard, especially hinge-lid boxes for cigarettes, the blanks are normally produced outside the packing machine and are supplied to said machine in the form of a blank stack. The packing machine is provided with a blank magazine being arranged upright or slightly tilted and from which the blanks are successively extracted via an extraction opening. The individual blanks a are then conveyed to a folding aggregate (folding turret) for further machining.
Hitherto, several so-called transfer rollers are generally used for extracting the individual blanks from the blank magazine. These consist of a roller or drum, which holds the blank to be extracted along its periphery and which is moved about its own axis and is moved to and fro (translationally) underneath the extraction opening, approximately parallel to the plane of said opening. The blank is transferred from the periphery of the transfer roller to a conveyor. This extraction process at the same time causes the blanks to be turned over, so that in the blank magazine, the bottom side of the blank is facing upwards.
The known aforementioned transfer rollers are complicated, trouble-prone and relatively slow-working means for extracting the blanks. A relatively large amount of time is needed for the extraction process because of the combined roll and transverse motion. With packing machines of very high performance, this leads to bottle-necks in this area of production.